Justification:
Listed as Vulnerable because it is known from fewer than five locations, and its Area of Occupancy is less than 20 km2, and population declines are plausible without ongoing intensive conservation efforts. The pathogen Batrachochytrium dendrobatidis has been detected in reintroduced captive-bred populations, and it is plausible that severe population declines could take place in the future.

This species is restricted to the Sierra Tramuntana of northern Mallorca, Balearic Islands, Spain. The present altitudinal range is from 10-850 m asl. Its area of occupancy is less than 10km², but slowly increasing as a result of intensive conservation action.

The population is approximately 500-1,500 adult pairs (Gasc et al. 1997; Arnold 2003). There are approximately 25, mostly isolated, populations. The total population is slowly increasing following coordinated recovery efforts, following a long period of decline and near extinction. The current increase, which probably started around the time that the first re-introductions were made in 1989, has been maintained even during years of drought, notably in 1999-2000. The population trend in this species is monitored through annual tadpole counts, the counts for 2004 (over 30,000 tadpoles) being the highest on record. The increase in numbers in established populations is not dependent upon continued re-introductions. However, it is unlikely that new populations would be established without re-introductions.

It is currently found only in small streams deeply carved into limestone mountains. The presence of the species is positively associated with steep slopes. Breeding takes place in the small streams that persist as pools in summer. A few populations occur by man-made water sources (cattle troughs, containers, rain tanks etc.) in open mountainous country; these are within the river basins of nearby canyon-living populations. Animals are generally found in rock crevices and under stones. This species does not tolerate serious habitat degradation. The distribution of predators on the species is negatively associated with elevation, and reproductive success is positively associated with elevation.

The major threats are predation by the introduced Viperine Snake (Natrix maura), and competition for space with Perez's Frog (Rana perezi). Development of tourism and human settlements, specifically the increased need for water resources (including damming and canalization of streams), is an additional threat. The threats are not likely to decrease, and so the current recovery programme needs to be continued more or less indefinitely. One isolated re-introduced population was impacted by an unidentified non-fungal disease in 2002 which killed some tadpoles. This disease did not recur in 2003 and 2004. Chytridiomycosis has been identified in the wild population, with the source of this chytrid infection traced to reintroduced captive-bred animals from Jersey Wildlife Preservation Trust, UK (Walker et al. 2008).

The species is protected by sub-national and national legislation. It is listed on Appendix II of the Bern Convention, on Annexes II and IV of the EU Habitats Directive, and on the national and sub-national Red Data Books. It is present in the protected areas of the Tramuntana mountains. The Balearic Government and Jersey Wildlife Preservation Trust have undertaken captive-breeding, re-introduction and other conservation initiatives. At least 10 populations have been successfully reintroduced. Re-introductions of animals from the Jersey Wildlife Preservation Trust stopped in 2002, but a new captive-breeding facility now exists on Mallorca, and re-introductions are expected to resume. However, as a result of the recent discovery of disease, a recommendation was made in 2004 to the Balearic Government to halt the re-introduction programme. A new recovery programme for the species is now being developed. There is a need to closely monitor populations of this species, especially with regard to the recent detection of the chytrid fungus Batrachochytrium dendrobatidis in introduced animals (Walker et al. 2008). A systematic programme is in place to remove Natrix maura from the range of the species.